Field of the Invention
The present invention relates to an optical semiconductor device and a method of fabricating an optical semiconductor device.
Related Background Art
Optical semiconductor devices are represented by wavelength-tunable semiconductor lasers, and in order to control the refractive index of a target portion in a wavelength-tunable semiconductor laser, the temperature of the target portion may be controlled to perform the tuning. Typically, a heater is used for the control of temperature, as described in Japanese Patent Application Publication No. 2007-48988.